Two weeks ago Ravi Shukla (name changed) bought two Kingfisher Airlines economy class tickets for Rs12,000 for a return trip to Goa on February 22.

Two weeks ago Ravi Shukla (name changed) bought two Kingfisher Airlines economy class tickets for Rs 12,000 for a return trip to Goa on February 22.

Alarmed by reports of Kingfisher cancelling flights at the last minute, the Bandra-based dentist on Monday checked fares on other airlines and found that the journey would cost Rs7,500 more. Worse, he got a text message from the airline stating that his 5am flight on Wednesday was rescheduled to 4.15am. "Since I cannot afford the fare difference I am hoping that the Kingfisher flight does not get cancelled," said Shukla.

Hundreds of such travellers booked on Kingfisher either cancelled their trip or spent up to 25% more for tickets on other airlines.

On Monday, 16 Kingfisher Airlines flights out of the Mumbai airport catering to fliers across metro cities such as Delhi and tier II towns such as Ahmedabad were cancelled. "The airline's schedule is constantly changing. A passenger booked to travel on Friday is already getting updates about delay in flight status," said a Fort-based travel agent.

Worst-affected were business class travellers, who found it difficult to find seats on alternative airlines. Domestic airlines have only four to six business class seats per flight.

Tour operators said such travellers spend up to Rs15,000 per ticket. "Business class fliers don't want to risk missing appointments," said Jay Bhatia, western region chairman of the Travel Agents Association of India.

A Kingfisher Airlines spokesperson said the airline was unable to operate 15% of the 240 flights scheduled across its national network on Monday.

Until Sunday, the airline had said that the on-going flight disruptions were temporary as some of their aircraft were grounded owing to various reasons including bird hits. However, on Monday, it stated that it was unable to operate all its flights as its bank accounts had been frozen by tax authorities owing to pending dues.

"We are in dialogue with the tax authorities to agree on a payment plan and get the bank accounts unfrozen at the earliest. We are appealing to them to see reason that inconvenience to the travelling public is not in anybody's interests," said a spokesperson. He added its representatives would appear before the Directorate General of Civil Aviation (DGCA), the safety regulator, to submit a plan to restore the full schedule.